Piston ID Help Please
 

So I finally had the time (and guts) to take the head off the 930 so I can replace that dang headstud. Anyway, this is certainly my first time opening up a 930 motor firsthand, but these pistons don't look like anything in the books??? Can someone tell me is these are stock Euro 3.3L Turbo pistons and if not, what they are.
Thanks in advance...
http://forums.pelicanparts.com/uploa...1212879123.jpg

http://forums.pelicanparts.com/uploa...1212879148.jpg

http://forums.pelicanparts.com/uploa...1212879210.jpg

Sure look like stock 97mm Mahle flat top turbo pistons to me. I would be tempted to rering it from the looks of the rings.

aws

Definitely going to re-reing the one that I pull the cylinders off of... only question now is do I do all 6 or just stick to this side like the original plan. :(

Dang, now that I know they are stock, I feel even worse about doing any mods to this motor. I was hoping they were some aftermarket deal that the PO had installed. Oh well, guess I will have to think on that a bit.
While I am thinking, anyone have any advice on how to decarbon the piston without the use of a bead blaster? Is there a chemical way? I tried with simple green and a green scrubbie and wore out the green scrubbie :)
http://forums.pelicanparts.com/uploa...1212887904.jpg

I mask the piston skirts with duct tape and bead blast the top and ring lands.

You can use a scotch brite wheel but it takes much longer and the results are the same as with the bead blast method.

BTW...The pistons look to be stock 97mm 3.3 turbo pistons.

My suggestion would be to find someone in your area with a soda blaster and use that to properly clean the pistons, sans rings.

That will remove all the carbon without damaging or eroding any aluminum.

I have read great things about the soda blast method. Unfortunately I do not have one of those in my garage. I do have a bench grinder and a dremel tool though :) Might give the scotchbrite another try. I just thought that there might be some chemical out there to soften it up or dry it out so it flakes off. Guess nothing come easy :)